1. Field of the Invention
The present invention relates to a front body structure for a vehicle.
2. Description of Related Art
In general, the front body structure for a vehicle is designed so as to absorb a collision energy when at least one side member forming a fore-and-aft directional framework member of a front compartment collapses in the axial direction of the side member.
However, for reasons that the side member is not always formed straightly and a power unit (e.g. heavy engine, drive motor) is attached to the side members, there is a possibility that the side members are deformed in bending at the vehicle collision.
Additionally, when the vehicle has an offset front collision, a problem arises in the impossibility of absorbing a collision energy sufficiently since a collision input (load) concentrates on one side member. In order to solve the above problem, Japanese Patent Application Laid-open No. 9-119322 discloses a structure that is directed to increase the absorption of collision energy at the vehicle front collision. In the structure, there is provided a large-sized subframe by which vehicle unit components (e.g. power unit, suspension parts, etc.) are suspended. In assembling, the subframe is attached to the side members from the underside of the vehicle. With the above arrangement, when the vehicle has a front collision, not only the side members but also the subframe is simultaneously deformed to increase the absorption of collision energy.
Note, the subframe forming the above structure includes a left side frame and a right side frame, which will be often referred “left-and-right side frames” hereinafter, a front cross member connecting the front sides of the side members with each other and a rear cross member connecting the rear ends of the side members with each other. With these constituents, the subframe is shaped to be rectangular in plan view, with a width substantially equal to a distance between the left side member and the right side member (referred “left-and-right side members” hereinafter). Further, the subframe is provided, at four corners thereof, with mount parts through which the subframe is secured to the underfaces of the left-and-right side members.